The present invention relates to mechanisms for closing vehicle trunk lids or engine compartment hoods and particular to mechanisms for closing the type of lids or hoods which are movably supported on what is known as four-link hinges.
Vehicles are being produced today with short trunk lids movably supported on a type of hinge mechanism referred to as a four-link hinge. This hinge allows a trunk lid to move with a wide angle, meeting styling and final user demands. The specific geometry of this hinge makes the trunk lid travel not on an arc about a fixed pivot, but rather about a specific curve established by the links of the hinge. This hinge geometry makes the power activation of the trunk lid difficult, not only because of the curvature of the movement, but because of the high loads on the hinge mechanism. One known way of driving this kind of trunk lid mechanism is to apply the torque directly to one of the crank links of the hinge mechanism. Mercedes Benz has accomplished this on luxury vehicles using a powerful, but expensive hydraulic drive system.